Support Matrix for Spill Containment Pan

ABSTRACT

A support matrix especially adapted for use with a spill containment pan having a reservoir defined by upstanding walls having upper edges and a generally flat-bottomed wall includes a porous grate that bridges the reservoir, a connection between the grate and the upper edges of the upstanding walls, and support walls connected to the grate and depending therefrom, the support walls having portions that contact the flat-bottomed wall. The lower edges of the support walls may be provided with cut-out portions that permit fluid to flow from one side of the support walls to the other. The support matrix is modular in nature so that one or more can easily be inserted into and removed from the reservoir.

REFERENCE TO RELATED APPLICATION

The present application incorporates by reference, and claims priority from, U.S. provisional patent application Ser. No. 61/291,139, entitled Support Matrix for Spill Containment Pan, filed Dec. 30, 2009 by Merrill E. Bishop.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to pans that collect spilled chemical materials and, more particularly, to a technique that enables vehicles to drive over the pans.

2. Description of the Prior Art

Traditionally, railroad tank car loading and unloading has been relatively unregulated. In the past, railroad sidings reflected that lack of concern because they had no provision to collect accidental discharges of whatever was being loaded and unloaded. Often the commodity being shipped was inexpensive or perceived to be of little environmental impact, and therefore any spills were either hosed down or just left for the next rain to clear away. With the advent of stiff fines and high soil remediation costs, techniques to prevent spills or eliminate adverse environmental consequences have become important.

In response to these concerns, spill containment pans have been provided to collect and possibly economically reuse spilled chemicals. For example, spill containment pans with convertible lidded structures are known in the art as taught in U.S. Pat. Nos. 5,052,422 and 4,651,887. An improved spill containment apparatus is disclosed in U.S. Pat. No. 5,435,458, issued Jul. 25, 1995 to Merrill E. Bishop, the disclosure of which is incorporated herein by reference (referred to herein as “the Multi-Pan patent”). In the Multi-Pan patent, three separate spill containment pans are disclosed—a center pan disposed between the rails and outboard pans disposed outside each of the rails. The pans have movable covers that prevent dirt or rainwater from entering the pans when the covers are in the closed position. When the covers for the outboard pans are opened, the covers become deflection panels that provide additional spill directing surfaces. The cover for the center pan slides longitudinally of the railroad tracks, on special rails, to cover or uncover the center containment pan.

U.S. Pat. No. 5,975,332, issued Nov. 2, 1999 to Merrill E. Bishop and U.S. Pat. No. 5,775,869, issued Jul. 7, 1998 to Merrill E. Bishop, the disclosures of which are incorporated herein by reference (referred to herein as “the Transportable Pan patent” and “the Compact Pan patent, respectively”), disclose additional spill containment pans especially adapted for use with railroad tank cars. All of the spill containment pans in question have a reservoir portion adapted to be disposed centrally between the rails or adjacent to the rails of a railroad siding or other suitable location.

In order to prevent the undesired ingress of water, dirt, or other environmental contaminants during periods of non-use, each of the Multi-Pan patent, the Transportable Pan patent and the Compact Pan patent disclose a pan that includes a cover. The cover is movable from a first position in which the reservoir is covered to a second position in which the reservoir is exposed.

Although the devices disclosed in the Multi-Pan patent, the Transportable Pan patent, and the Compact Pan patent provide many advantages compared with prior art spill containment pans, these devices do not address the issue of driving a vehicle over the pans. That is, the pans may be disposed at railroad sidings or other locations where it may be necessary or desirable to drive a vehicle over the pans. The covers used with these pans generally are not suitable to sustain the weight of a vehicle, especially a heavy truck. Moreover, if the covers are in the extended position, it would be undesirable for a vehicle to attempt to drive over the pan because the vehicle would have to traverse the reservoir. Not only would such traversal risk damage to the pan and/or the vehicle, it is possible that the reservoir would contain fluid contaminants that could contaminate or otherwise harm the vehicle.

Various attempts have been made to permit vehicles to traverse spill containment pans or similar structures. Such attempts usually have taken the form of removable grates or grills. See, for example, U.S. Pat. No. 5,359,955; U.S. Pat. No. 5,569,372; U.S. Pat. No. 5,579,700; U.S. Pat. No. 5,642,834; U.S. Pat. No. 6,415,987; and U.S. Pat. No. 7,316,834, the disclosures of which are incorporated herein by reference. While the '834 patent mentions that the grate disclosed therein is strong enough to be driven upon, the referenced patents do not disclose devices that would be suitable for use with spill containment pans such as those disclosed in the Multi-Pan patent, the Transportable Pan patent, and the Compact Pan patent.

Despite the teachings of the prior art, there remains a need for a support matrix that will permit a vehicle to drive over a spill containment pan. More specifically, any such support matrix should permit fluid flow out of the pan when desired. Any such support matrix preferably would not depend on upstanding support structure in the pan to provide enough strength to support a vehicle and would be usable with pans made of different materials, such as steel or polyethylene. Further any such support matrix desirably would be available as part of an originally manufactured pan or as an after-market product that can be installed simply by placing the support matrix into a pan. Yet additionally, any such support matrix preferably could be removed easily from the pan for cleaning or repair of either the support matrix or the pan.

SUMMARY OF THE INVENTION

In response to the forgoing and other concerns, the present invention provides a new and improved support matrix for use with a spill containment pan. The pan can be of any type, although the support matrix is particularly effective with pans used in conjunction with railroad tank cars. Any such pan will have a reservoir portion defined by upstanding walls and may be provided with one or more covers similar to those disclosed in the Multi-Pan patent, the Transportable Pan patent, and the Compact Pan patent. If pans of the referenced type are used, it is expected that they will be disposed centrally between or adjacent to the rails of a railroad siding and may in fact be permanently disposed between or adjacent to the rails at the siding. A characteristic of pans of the referenced type is that the reservoir is flat-bottomed and does not contain upstanding structure that might impede the drainage of the pan through a drain opening formed in one of the walls or the bottom of the pan.

The support matrix according to the present invention includes a porous upper surface, or grate, that bridges the reservoir. The grate preferably is defined by parallel spaced-apart metal bars or straps that form openings through which fluid can pass. The grate may be wide enough to rest upon the upper edges of the walls of the reservoir or flanges that extend therefrom, or the grate may be provided with laterally extending flaps or tabs for that purpose.

The grate is supported by depending walls positioned about its periphery and one or more optional support walls that suspend or otherwise depend from a central portion of the grate. The grate may be configured to the approximate dimensions of the reservoir such that one support matrix is used with the reservoir. Alternatively, several matrices may be provided for each reservoir, in which event the support matrices serve as modules that can be inserted into and removed individually from the reservoir.

The walls of the support matrix may be straight-sided with lower edges that lie in a common plane to rest on the flat-bottomed wall of the reservoir. Alternatively, the walls may be provided with upper and/or lower laterally extending flaps or tabs that increase the surface area that engages the grate or rests on the floor of the reservoir. The lower edges of certain of the walls are provided with cut-out portions. The cut-out portions permit any fluid contained within the support matrix to flow out of the support matrix whenever it is necessary to drain the reservoir.

The support matrix according to the present invention permits a vehicle to drive over a spill containment pan and permits fluid to be drained from the pan when desired. The support matrix does not require upstanding support structure in the pan to provide enough strength to support a vehicle and is usable with pans made of different materials, such as steel or polyethylene. Due to its modular nature, the support matrix according to the invention can be made available as part of an originally manufactured pan or as an after-market product that can be installed simply by placing the support matrix into a pan. Because the support matrix can be used merely by placing it into a pan, it can be removed easily from the pan for cleaning or repair of either the support matrix or the pan.

The foregoing and other features and advantages of the invention will be apparent from the description and claims that follow, taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a railroad siding showing a railroad tank car positioned above a spill containment pan according to the prior art;

FIG. 2 is a perspective view of a spill containment pan in which a support matrix according to the present invention is disposed;

FIG. 3 is a an enlarged view of a portion of FIG. 2; and

FIG. 4 is a perspective view of a spill containment pan in which a number of support matrices according to the invention are disposed.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, a railroad transfer station, or siding, is indicated by the reference numeral 10. At the siding 10, chemical materials are loaded into, or unloaded from, a railroad tank car 12. As used herein, the term “car” is intended to encompass any railed or wheeled vehicle that can be loaded or unloaded at a railroad siding. The car 12 includes a top opening 14 through which chemicals can be loaded into the car 12. The top opening 14 is accessible by way of permanently mounted ladders 16 that are connected to a superstructure 18. The car 12 includes a bottom opening 20 through which chemicals can be unloaded from the car 12 through a hose 22. As is conventional, the car 12 includes trucks 24 having wheels 26. The wheels 26 ride upon parallel rails 28, 30 which are secured to ties 32.

Continuing to refer to FIG. 1, spill containment apparatus according to that disclosed in the Compact Pan patent is indicated generally by the reference numeral 40. The apparatus 40 is in the form of a pan that has a bottom wall, opposed sidewalls, and opposed endwalls. Together, the bottom wall, the sidewalls, and the endwalls define a reservoir 48. The upper periphery of the sidewalls and the endwalls defines a top opening through which inadvertently spilled chemicals can be directed into the reservoir 48.

As will be apparent from an examination of FIG. 1, the pan 40 is rectangular such that it will fit between the rails 28, 30 of the siding 10. The bottom wall rests atop the ties 32. The pan 40 includes four NPT half-couplings (not shown) that project from the endwalls. The half-couplings are closed by removable NPT plugs (not shown). Upon removal of the plugs and connection of the half couplings to suitable piping (not shown), the reservoir 48 can be drained or pumped of its contents.

The pan 40 includes a cover that has first and second sections 62, 64 that are disposed adjacent to each other in the closed position. One of the sections 62, 64 overlaps the other to provide a sealing function. The sections 62, 64 are movable away from each other parallel to the rails 28, 30 to expose the reservoir 48. The pan 40 includes a plurality of flaps 92 that are movable from a stowed or closed position to an extended or open position (FIG. 1). The flaps 92 provide a continuous surface in the open position for directing any spills into the reservoir 48. The pan 40 also includes a movable platform 106 for workers to kneel on while connecting or disconnecting the hose 22 from the underside of the car 12. The platform 106 is made from a sheet of expanded metal that is supported by a rectangular frame and vertically extending legs. The width of the platform 106 is such that the flaps 92 can close completely for storage inside the reservoir 48.

In use, the flaps 92 and the cover are closed, and a car 12 is positioned above the pan 40 at the siding 10. The sections 62, 64 are opened to that position shown in FIG. 1 and then the flaps 92 are opened. The hose 22 is connected to the bottom opening 20 and the unloading operation then is conducted. Any inadvertent spills will fall directly into the reservoir 48 or will be deflected by the flaps 92 and directed into the reservoir 48. After the unloading operation has been completed, the foregoing steps can be reversed in order to permit the car 12 to be moved from the siding 10.

The spill containment pan according to the Compact Pan patent provides a number of advantages. An important advantage is that it is relatively inexpensive because it is constructed largely from readily available materials such as 3/16-inch sheet steel and 3/16-inch or ¼-inch angle iron. Unfortunately, such materials are not strong enough to permit a vehicle to drive across the pan 40 when the cover sections 62, 64 are closed. Similarly, when the cover sections 62, 64 are open, the platform 106 is not strong enough to permit a vehicle to drive across the reservoir 48. Also, the platform 106 is not large enough to support the spaced-apart wheels of a vehicle.

Referring now to FIGS. 2-4, the present invention is in the form of a support matrix 100 that can be disposed within a spill containment pan 102 that is similar to spill containment pan 40. The pan 102 includes upstanding side walls 104, end walls 105, and a floor 107 that define a reservoir 108. Ledges 110 extend laterally from the upper edge of side walls 104 and provide a place to attach covers or flaps (not shown) or similar structure. The pan 102 includes NPT half-couplings 112 that project from the end walls 105. Alternatively, in appropriate circumstances, the half-couplings 112 could project from the underside of the floor 107. The half-couplings 112 are closed by removable NPT plugs 114. Upon removal of the plugs 114 and connection of the half couplings 112 to suitable piping such as the hose 22, the reservoir 108 can be drained or pumped of its contents.

The support matrix 100 includes a porous upper surface, or grate 116, that bridges the reservoir. The grate 116 preferably is defined by parallel spaced-apart metal bars or straps 118 that form openings 120 through which fluid can pass. Grates 116 that are suitable for both pedestrian and vehicular traffic are commercially available from a number of sources, including McNichols Company, Tampa, Fla. The grate 116 can be wide enough so that it extends over, and rests upon, the upper edge of the side walls 104 and/or the ledges 110 (FIG. 2). If desired, one side of the grate 116 can extend over one of the ledges 110 while the other side does not extend over the other ledge 110 (FIG. 3). If desired, the grate 116 may be provided with laterally extending flaps or tabs (not shown) that rest upon the ledges 110 or the upper edges of the side walls 104.

The grate 116 is supported by depending walls 122 positioned about its periphery and one or more optional support walls 124 that suspend or otherwise depend from a central portion of the grate 116. The grate 116 may be configured to the approximate dimensions of the reservoir 108 such that one support matrix 100 is used with the reservoir 108. Alternatively, several matrices 100 may be provided for each reservoir 108, in which event the support matrices 100 serve as modules that can be inserted and removed individually from the reservoir 108.

The walls 122, 124 of the support matrix may be straight-sided with lower edges that lie in a common plane to rest on the flat-bottomed reservoir 108. Alternatively, the walls 122, 124 may be provided with upper and/or lower laterally extending flaps or tabs that increase the surface area that engages the grate 116 and/or rests on the floor of the reservoir 108. Walls 122, 124 with lower laterally extending flaps or tabs would be useful for preventing damage to pans made of structurally weak materials such as polyethylene. Upper, laterally extending flaps 126 can be seen in FIG. 4. If desired, walls 122, 124 could be in the form of box beams, I-beams, or other suitable shapes.

The lower edges of the walls 122, 124 are provided with cut-out portions 128. The cut-out portions 128 permit any fluid contained within the support matrix 100 to flow out of the support matrix 100 whenever it is necessary to drain the reservoir 108. The cut-out portions 128 are shown as semi-circles, although other shapes can be used provided they permit adequate fluid drainage without excessively weakening the walls 122, 124.

The support matrix 100 according to the present invention permits a vehicle to drive over a spill containment pan and permits fluid to be drained from the pan when desired. The support matrix 100 does not require upstanding support structure in the pan to provide enough strength to support a vehicle and is usable with pans made of different materials, such as steel or polyethylene. Due to its modular nature, the support matrix 100 according to the invention can be made available as part of an originally manufactured pan or as an after-market product that can be installed simply by placing the support matrix 100 into a pan. Because the support matrix 100 can be used merely by placing it into a pan, it can be removed easily from the pan for cleaning or repair of either the support matrix 100 or the pan.

Although the invention has been described in its preferred form with a certain degree of particularity, it will be understood that the present disclosure of the preferred embodiment has been only by way of example, and that various changes may be resorted to without departing from the true spirit and scope of the invention as hereinafter claimed. It is intended that the patent shall cover, by suitable expression in the appended claims, whatever degree of novelty exists in the invention disclosed. 

1. A support matrix especially adapted for use with a spill containment pan having a reservoir defined by upstanding walls having upper edges and a generally flat-bottomed wall, comprising: a porous grate that bridges the reservoir; a connection between the grate and the upper edges of the upstanding walls; and support walls connected to the grate and depending therefrom, the support walls having portions that contact the flat-bottomed wall.
 2. The support matrix of claim 1, wherein the grate is defined by parallel spaced-apart metal bars or straps that form openings through which fluid can pass.
 3. The support matrix of claim 1, wherein the connection between the grate and the upper edges of the upstanding walls is made by the periphery of the grate.
 4. The support matrix of claim 1, wherein the connection between the grate and the upper edges of the upstanding walls is made by flaps or tabs that extend laterally from the grate and which in use rest upon the upper edges of the upstanding walls.
 5. The support matrix of claim 1, wherein the support walls are positioned about the periphery of the grate.
 6. The support matrix of claim 1, wherein the support walls suspend or otherwise depend from a central portion of the grate.
 7. The support matrix of claim 1, wherein the support walls are positioned about the periphery of the grate and one or more support walls are suspended or otherwise depend from a central portion of the grate.
 8. The support matrix of claim 1, wherein the support walls are straight-sided with lower edges that lie in a common plane to rest upon the flat-bottomed wall.
 9. The support matrix of claim 8, further including tabs or flanges that extend laterally from the lower edges of the support walls and that rest upon the flat-bottomed wall.
 10. The support matrix of claim 8, further including tabs or flanges that extend laterally from the upper edges of the support walls and that are connected to the grate.
 11. The support matrix of claim 1, wherein the lower edges of selected support walls include one or more cut-out portions that permit fluid to flow from one side of the support wall to the other.
 12. The support matrix of claim 1, wherein the grate is configured to the approximate dimensions of the reservoir such that one support matrix is used with the reservoir.
 13. The support matrix of claim 1, wherein the grate is smaller than the approximate dimensions of the reservoir such that several support matrices are provided for each reservoir, whereby the support matrices serve as modules that can be inserted into and removed individually from the reservoir.
 14. A support matrix especially adapted for use with a spill containment pan having a reservoir defined by upstanding walls having upper edges and a generally flat-bottomed wall, comprising: a porous grate that bridges the reservoir and that is formed of parallel spaced-apart metal bars or straps that form openings through which fluid can pass; a connection between the grate and the upper edges of the upstanding walls, the connection between the grate and the upper edges of the upstanding walls being made by a selected one of the periphery of the grate or flaps or tabs that extend laterally from the grate and which in use rest upon the upper edges of the upstanding walls; and support walls connected to the grate and depending therefrom, the support walls being straight-sided and having lower edges that lie in a common plane and that contact the flat-bottomed wall, the support walls being positioned about the periphery of the grate and including one or more support walls that are suspended or that otherwise depend from a central portion of the grate, and wherein the lower edges of selected support walls include one or more cut-out portions that permit fluid to flow from one side of the support wall to the other.
 15. The support matrix of claim 14, further including tabs or flanges that extend laterally from the lower edges of the support walls and that rest upon the flat-bottomed wall.
 16. The support matrix of claim 14, further including tabs or flanges that extend laterally from the upper edges of the support walls and that are connected to the grate.
 17. The support matrix of claim 14, wherein the grate is configured to the approximate dimensions of the reservoir such that one support matrix is used with the reservoir.
 18. The support matrix of claim 14, wherein the grate is smaller than the approximate dimensions of the reservoir such that several support matrices are provided for each reservoir, whereby the support matrices serve as modules that can be inserted into and removed individually from the reservoir. 